Kernel: Make self-contained locking smart pointers their own classes

Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:

- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable

This patch renames the Kernel classes so that they can coexist with
the original AK classes:

- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable

The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.

AK/IntrusiveDetails.h

@@ -8,6 +8,9 @@
 
 #include <AK/NonnullRefPtr.h>
 
+#ifdef KERNEL
+#    include <Kernel/Library/LockRefPtr.h>
+#endif
 namespace AK::Detail {
 
 template<typename T, typename Container>
@@ -20,6 +23,13 @@ struct SubstituteIntrusiveContainerType<T, NonnullRefPtr<T>> {
     using Type = RefPtr<T>;
 };
 
+#ifdef KERNEL
+template<typename T>
+struct SubstituteIntrusiveContainerType<T, NonnullLockRefPtr<T>> {
+    using Type = LockRefPtr<T>;
+};
+#endif
+
 template<typename Container, bool _IsRaw>
 struct SelfReferenceIfNeeded {
     Container reference = nullptr;